1. Field of the Invention
The present invention relates generally to the field of optical reading devices. More specifically, the present invention relates to the calibration of projected target points in images captured by a miniature camera into an optical reading device just after assembly or during normal use.
2. Description of Related Background Art
Computer technology has made large amounts of information readily available. Electronic information sources may be found on storage media or storage devices such as hard drives, CD-ROMs, DVD-ROMs, etc., on a local computer, on a local computer network or a global computer network, such as the Internet. Electronic information may also be stored in bar codes, such as one or two dimensional bar codes.
Bar codes are placed on components, equipment, inventory items, packaging, and within printed documents. A bar code is scanned by an optical reader device to retrieve information associated with the bar code. The information may relate to an associated item, document, or reference. Bar codes may also enable access to commonly used web sites, email addresses, and even program applications or data files. Bar codes may be created by various applications that allows for convenient use by professionals, office users, and home consumers. Bar codes and optical reader devices provide useful methods for how information is captured, processed, and transmitted. Image based scanning by relatively low-cost optical devices is used in a wide range of data networking and data management services.
Optical reader devices may be manufactured relatively inexpensively and are adaptable to a variety of different environments. To ensure quality and performance, optical reader devices are assembled under tight tolerances. A user tests the alignment of an optical reader device by projecting a targeting symbol onto a specified bar code that is located adjacent several bar codes on a printed plane. The user then activates the reading of the specified bar code by the optical reader device. The user verifies whether the specified bar code at which the optical reader device is aimed is the code actually read. If the outcome is negative, then the optical reader device is mechanically readjusted until the outcome is positive.
If sufficient tolerance of the optical reader device can be maintained, then testing may be avoided. However, such tolerance is not always assured and mechanical readjustment is a time consuming and tedious process. Thus, it would be beneficial to provide an optical reader device that eliminated the need for mechanical readjustment. Such a device is disclosed and claimed herein.